// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef MEDIA_BASE_FAKE_SINGLE_THREAD_TASK_RUNNER_H_
#define MEDIA_BASE_FAKE_SINGLE_THREAD_TASK_RUNNER_H_

#include <map>

#include "base/callback.h"
#include "base/macros.h"
#include "base/single_thread_task_runner.h"
#include "base/test/simple_test_tick_clock.h"

namespace media {

class FakeSingleThreadTaskRunner : public base::SingleThreadTaskRunner {
public:
    explicit FakeSingleThreadTaskRunner(base::SimpleTestTickClock* clock);

    void RunTasks();

    // Note: Advances |clock_|.
    void Sleep(base::TimeDelta t);

    // base::SingleThreadTaskRunner implementation.
    bool PostDelayedTask(const tracked_objects::Location& from_here,
        const base::Closure& task,
        base::TimeDelta delay) final;

    bool RunsTasksOnCurrentThread() const final;

    // This function is currently not used, and will return false.
    bool PostNonNestableDelayedTask(const tracked_objects::Location& from_here,
        const base::Closure& task,
        base::TimeDelta delay) final;

protected:
    ~FakeSingleThreadTaskRunner() final;

private:
    base::SimpleTestTickClock* const clock_;

    // A compound key is used to ensure FIFO execution of delayed tasks scheduled
    // for the same point-in-time.  The second part of the key is simply a FIFO
    // sequence number.
    using TaskKey = std::pair<base::TimeTicks, unsigned int>;

    // Note: The std::map data structure was chosen because the entire
    // cast_unittests suite performed 20% faster than when using
    // std::priority_queue.  http://crbug.com/530842
    std::map<TaskKey, base::Closure> tasks_;

    bool fail_on_next_task_;

    DISALLOW_COPY_AND_ASSIGN(FakeSingleThreadTaskRunner);
};

} // namespace media

#endif // MEDIA_BASE_FAKE_SINGLE_THREAD_TASK_RUNNER_H_
